1. Field of the Invention
This invention relates to a chocolate product comprising a hard butter.
2. Prior Art
Chocolates are prepared by using, for example, cacao mass, cocoa butter, sugar and milk powder as starting materials. Various hard butters have been employed as a substitute for cocoa butter which is expensive and supplied in an unstable manner. The application of these hard butters, which are not only inexpensive but also enable the control of the melting point of a chocolate product, has been spreading with the recent diversification of chocolate products.
Hard butters are classified into tempering type and nontempering type. Nontempering type hard butters include lauric hard butters comprising lauric acid as the main constituting fatty acid and nonlauric ones comprising a trans form unsaturated fatty acid as the main constituting fatty acid.
These hard butters are mainly employed in the production of mold-type chocolates obtained by molding, coating or enrobing chocolates used for coating cakes or biscuits, soft chocolates, white chocolates and colored chocolates.
A chocolate product comprising cocoa butter or a hard butter would seem as if it were coated with white powder upon storage, in .particular, under wide fluctuations of temperature. This phenomenon is called fat bloom and significantly damages the commercial value of the product.
It is believed that this fat bloom is caused by the conversion of fat microcrystals into coarse ones.
Fat bloom is frequently observed, in particular, in a chocolate products comprising a lauric hard butter. For example, the surface of such a chocolate product comprising a lauric hard butter together with cocoa butter in an amount of only 5% or less of the total fat components would be coated with white spots, i.e., fat bloom, upon prolonged storage. Further, fat bloom is observed in a white or colored chocolate free from any cocoa powder and significantly lowers the commercial value of the same. Furthermore, fat bloom is frequently observed in a chocolate product comprising a nonlauric hard butter which contains 20 to 30%, based on the total fat components, of cocoa butter in order to improve the flavor of the product.
There has been attempted to prevent fat bloom by, for example, improving a process for producing a chocolate, modifying a hard butter or adding an emulsifier as a fat bloom inhibitor. However, none of these method can give a satisfactory result.
JP-B-45-13428 (the term "JP-B" as used herein refers to an "examined Japanese patent publication") discloses a process for producing a milk chocolate by adding 0.1 to 2% by weight of a sucrose fatty acid ester having an HLB of 5 or below to a milk chocolate composition comprising a large amount, i.e., 20% or above on a solid basis of milk. This process aims at producing a chocolate product having no irritating taste originating from milk but an excellent flavor and a high meltability in mouth. According to the specification of this patent, the sucrose fatty acid ester to be used therein has an HLB of 5 or below and comprises bound fatty acids carrying 12 to 22 carbon atoms, though one comprising 70% of stearic acid and 30% of palmitic acid as constituting fatty acids is exclusively shown as an effective sucrose fatty acid ester in Examples. It has been proved in Examples of the present invention that the sucrose fatty acid ester having an HLB of 1 as shown in Example 2 of the above patent is ineffective in preventing fat bloom of a chocolate comprising a nontempering type hard butter.
JP-B-49-28990 discloses a process for producing a chocolate which shows no fat bloom and has a low viscosity, an excellent gloss and a high resistance to heat distortion. This process comprises a composition, which comprises a sucrose fatty acid ester having an HLB of 5 to 7 which is a mixture of mono-, di- or triesters of sucrose and higher fatty acids carrying 10 to 22 carbon atoms, lecithin, a fat of a high hardness and anhydrous glucose, to a chocolate comprising a tempered cocoa butter as a fat component. In contrast thereto, the sucrose fatty acid ester to be used in the present invention has an HLB of 2 or less and is effective in a chocolate comprising a nontempering type hard butter. In addition, it is unnecessary in the present invention to formulate the sucrose fatty acid ester into a composition.
Effects of sucrose fatty acid esters of lowering the viscosity of a chocolate are described in a report entitled "The Influence of Some Surfactants on the Viscosity of Confectionery Fat/Sugar Mixtures" (cf. Int. Chocolate Review, 24 (12), 478 (1969)). However, the sucrose fatty acid esters whose effects are examined in this report are mono- or diesters of a degree of substitution of 1 or 2 and none of sucrose fatty acid esters of a higher degree of substitution, i.e., 4 to 7 to be used in the present invention is discussed therein.
A decrease in the viscosity of a milk- or sweet-chocolate caused by adding a sucrose fatty acid ester thereto is discussed in a report entitled "The Effect of Sucrose Esters in Chocolate and Cocoa (cf. Int. Chocolate Review, 20 (4), 142 (1969)). However, the effects of only four sucrose fatty acid esters, i.e., Nitto Ester 1005, 1007, 1009 and 1011 are discussed therein. According to this report, Nitto Ester 1007 has an HLB of 7 and thus it is different from those having an HLB of 2 or below to be used in the present invention.
The roles of surfactants in chocolates and compound coating are described in a report entitled "Surfactants" (cf. The Manufacturing Confectioner", 105 (1987)). Although there is reported that a surfactant can impart a resistance against fat bloom to a chocolate, the sucrose fatty acid esters employed therein are simply called in the general name "sucrose fatty acid esters" and those having a specific constituting fatty acids, which are to be employed in the present invention, are not reported therein.